One of the most commonly confused products in the building materials industry is quarter sawn lumber. Simply stated, it’s actually just how a log is cut.
With plain sawn material the log is cut vertically as shown in the pictures above and below. This maximizes the yield out of a log with very little waste and you achieve the widest boards possible. When a log is plain sawn you are cutting vertically across the growth rings of the tree. This leaves an arched end grain that wants to force the board to cup when moisture enters and exits the board. Imagine a house load of white oak flooring laid out in a new home in our Cape Cod climate. Moisture will be constantly entering and exiting the boards and the potential for cupping is accelerated, especially in wider boards.
With quarter sawn material the log is literally quartered. A log is cut in quarters then sawn perpendicular to the growth rings of the tree. By cutting the log this way you have less yield out of a log, more waste and you are limiting the max width of the boards you can achieve from a log. So in a world of limiting waste, maximizing yield (and therefore profits) why would anyone quarter a log? Performance is the answer. As I mentioned earlier, the log is cut perpendicular to the growth rings of the tree. This leaves the end grain at a 90 degree angle to the face of the board. With quarter sawn material the boards cannot cup. In red & white oak quarter sawn (most commonly used for flooring on Cape) it also creates a gorgeous fleck pattern on the face of the board (see pic below). Quarter sawn red and white oak are truly superior products, especially when the end use is flooring and is located in the moisture rich climate we live in on Cape Cod.